Looks legit to me. Obviously there are other factors to consider when comparing chassis (hardpoint locations, hitboxes, etc) but I can see this data being a valuable resource.
We all knew this (or parts thereof by simple trial and build) but it's a very good writeup and collection of easily read materials. However, what this does not take into account is the relative value of mobility. It argues that the payload suffers by putting a standard 400 in a Boars Head and I am in total agreement there. But what of being able to outmaneuvre the enemy? What about twist speed that comes with larger engines? It's hard to completely cover all angles in theorycrafting. As usual, if something works for you then work that magic. This thread is still good at showing the limits.
where would the jester sit? you are saying/implying the sha-yu is ideal mech for lights and mediums? (40t, FF, ES, xl280 118kph= 17-14t free)
This i cannot disagree - a matter of fact. Best example is the Victor - I run STD320 if i use limited range weaponloadouts, XL350 if using long-mid range weaponloadout. The Speed Gain is little from 350+ Engines, so better put the weight into weapons and kill the enemies faster. One point should be mentioned - mounting XL Engines (and ES/FF) consumes more critslots so limiting the amount of Heatsinks. Cool Efficiency is more important for Heavies/Assaults than high Speed.
Looks similar to what skribs posted on mechspecs several months ago. (or is there anything new? I only had a brief look)
What Lan said. Ultimately, every experienced mechwarrior already knows this; the bigger the mech the heavier the engine required to go fast. Again, theory crafting is all great in what is "optimal" but it doesn't take in to account tactical requirements, weapon hardpoints, hardpoint locations, jump abilities etc. If the world of MWO (and MechWarrior/Battletech) was all just about the weight game you would see 4 mechs on the battlefield. 1 Optimal Light, 1 Optimal Medium, 1 Optimal Heavy and 1 Optimal Assault. This would get old and (even more) boring pretty quickly.
Skribs had a really interesting guide from a while back that showed similar data in a different manner. Unfortunately the graphs he included seem to be down. One of the main takeaways from both of these threads is that there is a huge dropoff in free weight when going with anything over a 300 engine, for both XL and STD engines.
There is also one aspect that nobody has mentioned in reply yet, and that is the critical space you can save by having heat sinks in the engine slot. I have had several builds where it made more sense to spend an extra ton on an engine, but then get to stuff another DHS in the engine to gain back 3 needed crit slots.
It really depends on the 'mech and role for me. LRM boats and snipers are always weapons-first designs, then I try and cram whatever engine and equipment I think I can get away with. Occasionally, I'll come up with a layout and see how it works on several chassis and variants. More rarely, I'll pick a 'mech and an engine, then see what I can get away with. Then I see how the build works on other 'mechs with similar speeds.
This is exactly what I did while making the Benefactors Video for the Grimm Skirmisher build. Grab a chassis and shoe-horn in the biggest engine I could THEN work the weapons that I wanted to use and that made sense to me.
After the XL 300 engine weight really starts going bonkers, difference between XL255-XL280-XL300 is always 1.5 tons, but XL300-XL325 is 3.5 tons. The weight differences between STD engines are obviously even higher. That's the reason the 300 engine rating is so good, it's the last one before the giant rampup. Of course, with larger mechs it might be too slow of an engine to get a decent torso twist limiting your maneuverability too much, which is more hurtful than the limited top speed imo. You'll get to the fight eventually, but how well you do in the fight is the twisting range and speed.
It's not quite an exponential function. XL 300 is right around the "elbow" part of the graph, where the nonlinearity becomes readily apparent. Since the tonnage values are quantized in half-ton increments it won't fit any exponential curve perfectly. Anything under a 240 is really sacrificing speed, anything over a 300 is sacrificing lots of weight.
From that conclusion, that means that engine sizes from 240-300 ON AVERAGE are good choices for Speed/Payload. But I know a few Victors and Battlemasters that say differently. Very interesting.
That is without mentioning that from 245 and lower (each 25 engine rating) you need to add 1 more ton to get 10 heatsinks, so low rating engines are actually even heavier (thus more speed sacrificing) than they appear. This is also why a 150kph Jenner can have such an extremely more deadly loadout than a 150 kph Locust, besides the tonnage difference, the engines don't get much lighter while they drop down in size, so there's even less tonnage to play with.
Aah, you're right. Forgot about that. Silly me. There, corrected it. The trend lines have a rather poor correlation with the graph, but that tells us some interesting things. They correlate well at the low ranges, then at around the 235-325 rating the engines are lighter than the exponential function would predict. After that the engines are MUCH heavier than expected for exponential growth. So the 235-325 zone is the ideal area, where you get "free" speed for your engine rating with STD engines. XLs cut out at about XL 310, but don't get terrible until the 360.
